Endoscopic procedures have been developed for observing and treating internal body organs. Such procedures involve the insertion of an endoscope into a natural body orifice or through an incision in the body which allows a surgeon to observe and treat tissue inside a body cavity. Flexible endoscopes have been developed for insertion into natural body orifices, e.g., through the mouth or into the rectum. Also, rigid endoscopes have been developed for insertion into the abdominal cavity or the thoracic cavity through incisions at the surface of the body. Typically, a trocar is inserted into a trocar sleeve or tube to facilitate the insertion of the trocar sleeve through an incision and its penetration through internal body tissue. After the trocar sleeve is positioned at a desired surgical site, the trocar is removed from the trocar sleeve to allow another instrument such as an endoscope or forceps to be inserted into the trocar sleeve and advanced into contact with the tissue at the surgical site. The observation and treatment of the tissue can be made difficult by large body organs, e.g., the liver, lungs or intestines, which must be displaced to provide access to the surgical site.
In the prior art, several types of instruments are known for manipulating internal body tissue. For example, U. S. Pat. No. 4,909,789 discloses observation assisting forceps including a set of expandable wires mounted on a shaft which is normally retracted into a sheath. When the shaft is advanced, the wires project out of the sheath and expand into a fan-shaped configuration in the same plane. The expanded wires can be used to set aside internal organs obstructing the observation with an abdominal cavity endoscope. The wires are provided at the tips with spherical members which prevent the organs from being hurt.
U. S. Pat. No. 4,654,028 discloses an incision opening expansion holder including a plurality of wires at the end of an inner tube which are three dimensionally expanded when projecting out of an outer tube to expand an incision of a blood vessel graft for purposes of inosculation. U.S. Pat. No. 4,705,041 discloses a tissue dilator comprising a catheter which supports an expandable member, e.g., a balloon or a scissor-like member. U. S. Pat. No. 1,878,671 discloses a dilator for opening a body cavity including an ovate head mounted on a wire received in a tube which is inserted into the body cavity. U.S. Pat. No. 4,655,219 discloses a tissue grasping accessory including a plurality of flexible grasping arms for use with an endoscopic instrument to grasp a tissue specimen. U.S. Pat. No. 4,590,938 discloses a device for removal of kidney stones through the working channel of an endoscope including a basket comprising four outwardly bowed, generally flat spring arms which are expandable into a bulbous shape and collapsed when retracted into a sheath. The relatively broad, flat surfaces of the spring strips deflect the kidney tissue surrounding the stone while the distally enlarged volume of the basket allows the surgeon to dislodge and capture the stone.
None of the above described devices are particularly suited for use in manipulating large body organs, e.g., the liver, lungs or intestines, away from a desired surgical site. Moreover, it appears that several of the devices may have a tendency to damage the tissue if attempted to be used to displace large body organs.
Accordingly, it is an object of the present invention to provide a tissue manipulator which is adapted to safely manipulate internal body tissue.
Another object of the invention is to provide a tissue manipulator for insertion through an endoscopic device to manipulate tissue such as large body organs in a body cavity.
It is also an object of the invention to provide an endoscopic tissue manipulator which is suitable for insertion through an endoscopic device into a body cavity for displacing or retaining large body organs, e.g., the liver, lungs or intestines, away from a desired surgical site.